English
Related papers

Related papers: Non-Equilibrium Spectrum Formation Affecting Solar…

200 papers

The evolution of the filamentation instability produced by two counter-streaming pair plasmas is studied with particle-in-cell (PIC) simulations in both one (1D) and two (2D) spatial dimensions. Radiation friction effects on particles are…

Plasma Physics · Physics 2015-09-16 M. D'Angelo , L. Fedeli , A. Sgattoni , F. Pegoraro , A. Macchi

Studies on small-scale jets' formation, propagation, evolution, and role, such as type I and II spicules, mottles, and fibrils in the lower solar atmosphere's energetic balance, have progressed tremendously thanks to the combination of…

Nonlinear single Compton scattering has been thoroughly investigated in the literature under the assumption that initially the electron has a definite momentum. Here, we study a more general initial state, and consider the electron as a…

High Energy Physics - Phenomenology · Physics 2016-05-04 A. Angioi , F. Mackenroth , A. Di Piazza

Context. The He i 1083 nm is a powerful diagnostic for inferring properties of the upper solar chromosphere, in particular for the magnetic field. The basic formation of the line in one-dimensional models is well understood, but the…

Solar and Stellar Astrophysics · Physics 2016-10-19 Jorrit Leenaarts , Thomas Golding , Mats Carlsson , Tine Libbrecht , Jayant Joshi

We study the formation of O I and OH spectral lines in three-dimensional hydrodynamic models of the solar photosphere. The line source function of the O I 777 nm triplet is allowed to depart from local thermodynamic equilibrium (LTE),…

Astrophysics · Physics 2007-05-23 Dan Kiselman , Åke Nordlund

The solar radiation spectrum is important for renewable energy harvesting, as well as climate and ecological systems analysis. In addition to seasonal/annual and diurnal oscillations, the signal is composed of different frequencies ($f$)…

Geophysics · Physics 2018-11-01 Golan Bel , Mahesh M. Bandi

The surface structure of the magnetic field in stars is one part of the information about the surface inhomogeneities like brightness, movement or chemical composition, which is contained in the integral radiation flux but distorted beyond…

Astrophysics · Physics 2007-05-23 E. Gerth , Yu. V. Glagolevskij

In the first three papers of this series, we investigated the formation of photospheric neutral iron lines in different atmospheres ranging from idealised flux tube models to complex three-dimensional magnetohydrodynamic (3D MHD)…

Solar and Stellar Astrophysics · Physics 2025-05-14 R. Holzreuter , H. N. Smitha , S. K. Solanki

The nonlinear optical behavior of quantum systems plays a crucial role in various photonic applications. This study introduces a novel framework for understanding these nonlinear effects by incorporating gauge-covariant formulations based…

General Physics · Physics 2025-03-11 Jingxu Wu , Chenjia Li

With the goal of producing a reliable set of model atoms and singly-ionized ions for use in building NLTE model atmospheres, we have combined measured energy levels, critically-compiled line transition probabilities, and resonance-averaged…

Astrophysics · Physics 2009-11-07 C. Allende Prieto , D. L. Lambert , I. Hubeny , T. Lanz

The issue of predicting solar flares is one of the most fundamental in physics, addressing issues of plasma physics, high-energy physics, and modelling of complex systems. It also poses societal consequences, with our ever-increasing need…

Solar and Stellar Astrophysics · Physics 2014-11-20 R. T. James McAteer , Peter T. Gallagher , Paul A. Conlon

Different simplified approaches are used to account for the non-local thermodynamic equilibrium (NLTE) effects with 3D hydrodynamical model atmospheres. In certain cases, chemical abundances are derived in 1D NLTE and corrected for the 3D…

Solar and Stellar Astrophysics · Physics 2016-02-17 J. Klevas , A. Kučinskas , M. Steffen , E. Caffau , H. -G. Ludwig

We consider in the article the influence of the irradiation and the internal sinks of the point defects on the rate of the flattening of the surface structure in solids. The irradiation produces only the additional external sources of point…

Materials Science · Physics 2007-05-23 V. M. Apalkov , Yu. I. Boiko , V. V. Slezov , H. D. Carstanjen

A semi-classical approach is used to calculate radiation emission in the collision of an electron with an intense focused laser pulse. The results are compared to predictions from the locally constant field and locally monochromatic…

Plasma Physics · Physics 2022-08-17 Christian F. Nielsen , Robert Holtzapple , Ben King

The propagation of stable coherent entities of an electromagnetic field in nonlinear media with parameters varying in space can be described in the framework of iterations of nonlinear integral transformations. It is shown that for a set of…

Pattern Formation and Solitons · Physics 2020-12-10 A. Yu. Okulov

The diagnosis of new high-resolution spectropolarimetric observations of solar prominences made in the visible and near-infrared mainly, requires a radiative modelling taking into account for both multi-dimensional geometry and complex…

Astrophysics · Physics 2015-05-13 L. Leger , F. Paletou

Atmospheric haze is the leading candidate for the flattening of expolanetary spectra, as it's also an important source of opacity in the atmospheres of solar system planets, satellites, and comets. Exoplanetary transmission spectra, which…

Earth and Planetary Astrophysics · Physics 2018-10-17 Z. Felfli , T. Karman , V. Kharchenko , D. Vrinceanu , J. F. Babb , H. R. Sadeghpour

A self-consistent approach to nonequilibrium radiation temperature is introduced using the distribution of the energy over states. We begin rigorously with ensembles of Hilbert spaces and end with practical examples based mainly on the far…

Statistical Mechanics · Physics 2009-11-07 Christopher Essex , Dallas C. Kennedy , R. Stephen Berry

Thermal nonequilibrium (TNE) is a condition of the plasma in the solar corona in which the local rate of energy loss due to radiation increases to the point that it cannot be sustained by the various heating terms acting on the plasma,…

Solar and Stellar Astrophysics · Physics 2024-11-27 Roger B. Scott , Jeffrey W. Reep , Mark G. Linton , Stephen J. Bradshaw

The magnetic field of the quiet-Sun chromosphere remains a mystery for solar physicists. The reduced number of chromospheric lines are intrinsically hard to model and only a few of them are magnetically sensitive. In this work, we use a 3D…

Solar and Stellar Astrophysics · Physics 2012-03-22 J. de la Cruz Rodríguez , H. Socas-Navarro , M. Carlsson , J. Leenaarts